The invention relates to a rolling sleeve-type gas spring with dust protection including a U-shaped sleeve disposed in a cylinder mounted on one of two spring components and rolling over a piston extending from the other component into the cylinder. Such gas springs are particularly suited for the wheel support arrangements of vehicles which however are exposed to dust and road dirt.
Such rolling sleeve-type springs are known, for example, from DE GM 1 816 597 and U.S. Pat. No. 4,722,516. In the first mentioned document, the dust protection comprises a bellows, which is mounted on the outside of the cylinder. Such a bellows, however, requires a relatively large amount of space around the air spring. In U.S. Pat. No. 4,722,516, the dust protection comprises an annular dirt shield disposed at the open end of the cylinder and slidingly engaging the piston. Such an arrangement, however, generates undesirable friction upon relative movement between the piston and the cylinder.
It is the object of the present invention to provide a rolling sleeve-type gas spring with dust protection which is space saving and subject to only little friction. In addition, venting provisions for venting the space between the gas pressurized rolling sleeve and the dust protection should be simple.